SECURITY at Crewe Station has been stepped up amid fears Al Qaeda terrorists could launch a devastating bomb attack on the British rail network.

Police and station managers are calling on those using the mainline station to be extra vigilant and report anyone seen acting suspiciously.

The warning comes amid growing concern the network's main passenger and signalling hubs could be targeted by Osama Bin Laden's Al Qaeda network.

The fundamentalist Islamic militants are thought to be behind last week's atrocity in Spain which left more than 200 people dead and 1,500 injured.

In a synchronised attack 10 bombs exploded on four trains packed with commuters at the height of the morning rush hour in and around the capital Madrid.

Now British Transport Police and a major rail workers' union say they fear the UK network could be a soft target singled out by terrorists.

Crewe Station is one of the main interchange stations for passengers travelling on the network with more than 10,000 people passing through its platforms each day.

Supt Miles Flood, of the British Transport Police, said: 'We would certainly ask members of the public to be vigilant while travelling through the station.

'We want people to let us know if they see people acting suspiciously on the network or if they see anything like bags and rucksacks left unattended.'

Supt Flood said there are 'stringent security measures in place' for the station that are 'constantly reviewed in accordance with emergency plans'.

He added: 'Passengers should be reassured that we are working closely with counter-terrorism officers and are doing all we can to protect their safety.'

Network Rail, which owns the station, said the platforms were watched by CCTV cameras and a security firm is also employed to work alongside the police.

Spokesman Keith Lumley said: 'Crewe Station is very much central to a lot of the network. It's quite a main interchange point for the West Coast Main Line and cross-country services. For that reason, it's a very important strategic location.'

Virgin Rail, which runs and manages Crewe Station on a day-to-day basis, said itreacts quicklytoanycounter-terrorism measures that are introduced.

Spokesman Dave Ewart said: 'We are working closely with the British Transport Police and the civilian police force and act upon any regulations introduced by the Government. We would emphasise the call for extra vigilance by members of the public.'